Main circuit of electric power generating apparatus for dispersed power supply

ABSTRACT

In an electric power generating apparatus for dispersed power supply using a permanent magnet type electric power generator having many kinds of windings in order to obtain the maximum output by force of wind without using PWM converter, there is a problem that gap magnetic flux of the permanent magnet type electric power generator is demagnetized to decrease the internal induced voltage because alternating current output of the permanent magnet type electric power generator is lagging current. In an electric power generating apparatus for dispersed power supply including a permanent magnet type electric power generator having a plurality of windings inducing different effective values of induced voltages and individual rectifiers for rectifying alternating current outputs of the permanent magnet type electric power generator, a capacitor is connected in series between the individual rectifier and the alternating current output terminal of the winding inducing higher effective value of induced voltage among the plurality of windings in a manner that serial impedances of the capacitor and the permanent magnet type electric power generator become capacitive within the range of rated rotational speed of said permanent magnet type electric power generator.

TECHNICAL FIELD

This invention relates to a main circuit of an electric power generatingapparatus for dispersed power supply, which derives from a permanentmagnet type electric power generator driven by a windmill or waterwheelsubstantially maximum output obtained by wind or water irrespective ofwind or water speed, and more particularly to a main circuit of anelectric power generating apparatus for dispersed power supply forperforming constant voltage charge from a permanent magnet type electricpower generator without using a PWM converter.

BACKGROUND ART

In order to obtain the approximately or substantially maximum outputfrom a permanent magnet type electric power generator connected to awindmill or waterwheel by converting alternating current to directcurrent without using a PWM converter, the applicant of the presentapplication had proposed an electric power generating apparatus fordispersed power supply comprising a permanent magnet type electric powergenerator including a plurality of windings inducing different inducedvoltages and having alternating current output terminals each connectedin series through a reactor to a rectifier, and the direct currentoutputs of these rectifiers being connected in parallel to one another,thereby outputting the direct current external (refer to, for exampleopened Japanese Patent Literature 1).

Such a prior art technique will be explained in detail with reference toa main circuit diagram illustrating an electric power generatingapparatus for dispersed power supply connected to a windmill shown inFIG. 13.

In FIG. 13, a windmill is denoted by reference numeral 1 and an electricpower generating apparatus for dispersed power supply of the prior artis denoted by reference numeral 2 comprising a permanent magnet typeelectric power generator 3, first and second reactors 4 and 5, first andsecond rectifiers 7 and 8, a positive output terminal 11 and a negativeoutput terminal 12. Reference numeral 13 denotes a battery.

The permanent magnet type electric power generator 3 in FIG. 13 has twokinds of windings and of a three-phase generator.

In the permanent magnet type electric power generator 3 in FIG. 13,connected to the first reactor 4 and further to the first rectifier 7 isthe alternating current output terminal W1 of a first winding whoseeffective value of induced voltage is low due to its smaller number ofturns.

Connected to the second reactor 5 and further to the second rectifier 8is the alternating current output terminal W2 of a second winding havinga larger number of turns.

The direct current outputs of the first and second rectifiers 7 and 8are connected in parallel to the positive output terminal 11 and thenegative output terminal 12, and the total output of the respectivewindings is stored into the battery 13.

A method for obtaining the substantially maximum output from theelectric power generating apparatus 2 for dispersed power supply thusconfigured will be described hereinafter.

FIG. 12 is a diagram for explaining the outline of the number ofrevolutions of the windmill versus output characteristic when wind speedis taken as the parameter.

With a windmill, if the shape of the windmill and wind speed U aredetermined, the output P of the windmill is monolithically determinedwith respect to the number of revolutions N of the windmill. Forexample, the output P of the windmill for the wind speeds Ux and Uy isillustrated as in FIG. 12, respectively. Peak values of the outputs P ofthe windmill for various wind speeds are shown as the maximum outputcurve Pt in FIG. 12.

In more detail, with the number of revolutions of the windmill versusoutput characteristic in FIG. 12, when the wind speed is Ux, the maximumoutput Px of the windmill is obtained at the number of revolutions Nx ofthe windmill as shown at the intersection point Sx of the windmilloutput curve at the wind speed Ux with the maximum output curve.

Moreover, when the wind speed is Uy, the maximum output Py of thewindmill at the wind speed Uy is obtained at the number of revolutionsNy of the windmill.

Namely, when viewing the maximum output curve in FIG. 12 from anotherpoint, this curve indicates the fact that in order to obtain the maximumoutput from the wind, upon the number of revolutions N of the windmillbeing determined, the maximum output can be obtained by primarilydetermining the output P of the permanent magnet type electric powergenerator 3 at a value on the maximum output curve Pt.

FIG. 11 is an explanatory view when the direct current outputs of theelectric power generating apparatus 2 for dispersed power supply of theprior art are connected to a constant voltage power supply such as abattery or the like. As shown in FIG. 11, respective outputs of thefirst and second windings of the permanent magnet type electric powergenerator 3 of the electric power generating apparatus 2 for dispersedpower supply are shown as the number of revolutions of windmill versusoutput characteristic curves P1 and P2 owing to difference in theeffective values of induced voltages of the windings and voltage dropscaused by internal inductances of the respective windings and thereactors connected to the respective output terminals.

In other words, when the number of revolutions N of the windmill is low,the battery 13 is not charged because the induced voltages of the firstand second windings in the permanent magnet type electric powergenerator 3 are lower than the battery voltage Vb.

However, when the number of revolutions N of the windmill increases to avalue near to N2, the electric current starts to flow through the secondwinding. With increase in number of revolutions N of the windmill, theelectric current increases so that the output of the second winding isas shown at P2.

At this time, even if the number of revolutions N of the windmillincrease to cause the induced voltage to be increased, the voltage ofthe battery remains at substantially constant value. On the other hand,the output P2 only gradually increases because the inductance of thesecond winding and the inductance by the second reactor 5 areproportional to the frequency.

With the first winding, when the number of revolutions N is furtherincreased, the output starts to be obtained and greater output can beobtained because the internal inductance of the first winding andinductance of first reactor 4 are both small.

FIG. 10 illustrates the output to a constant voltage power supply suchas a battery of the electric power generating apparatus for dispersedpower supply of the prior art.

A total output obtained by summing up the outputs P1 and P2 of the firstand second windings in the permanent magnet type electric powergenerator 3 is shown by an approximate output curve Ps.

Patent Literature 1: Japanese Patent Application Opened No. 2004-64,928(FIG. 1)

DISCLOSURE OF THE INVENTION Task to be Solved by the Invention

When electric power is obtained from the main circuit of the electricpower generating apparatus 2 for dispersed power supply configured asdescribed above, the alternating current output of the windings of thepermanent magnet type electric power generator 3 is lagging current sothat there is a tendency of gap magnetic flux of the permanent magnettype electric power generator 3 to be decreased. Therefore, thistendency would become an important cause for reducing the internalinduced voltage, thereby decreasing the output of the electric powergenerating apparatus 2 for dispersed power supply.

Particularly, the second winding having the larger number of turns willbe greatly affected by the influence of flux reducing effect which is inproportion to the product of lagging current and the number of turns ofthe winding owing to the large number of turns although the currentflowing through the second winding is small, while the first windingcannot output a large alternating current because of its small number ofturns.

Viewing the influence of the flux reducing or demagnetizing effect withrespect to the output to the constant voltage power supply such as thebattery of the electric power generating apparatus 2 for dispersed powersupply of the prior art in FIG. 10, it is clear that the difference Pzbetween the maximum output curve Pt and the approximate output curve Psbecomes great when the number of revolutions N of the windmill is large.

In order to mitigate the flux reducing or demagnetizing effect, forexample, it may be needed to increase the thickness of the permanentmagnets in the direction of magnetic flux in the permanent magnet typeelectric power generator 3.

The invention has been completed in view of the circumstances describedabove. The principal object of the invention is to provide a maincircuit of an electric power generating apparatus for dispersed powersupply, which enables the price of the permanent magnet type electricpower generator 3 to be reduced by decreasing the amounts of expensivepermanent magnets in the permanent magnet type electric power generator3 and enables a maximum output curve Pt and an approximate output curvePs to substantially coincide with each other, even when the number ofrevolutions N of the windmill is great.

Solution for the Task

Therefore, in a main circuit of an electric power generating apparatusfor dispersed power supply including a permanent magnet type electricpower generator driven by a windmill or waterwheel and having aplurality of windings inducing different effective values of inducedvoltages, alternating current outputs of which permanent magnet typeelectric power generator are rectified by individual rectifiers whosedirect current outputs are summed up to output to the external,according to the invention a capacitor is connected in series betweenthe individual rectifier and an alternating current output terminal ofthe winding inducing high effective value of induced voltage among theplurality of windings.

Effect of the Invention

The invention can provide a main circuit of an electric power generatingapparatus for dispersed power supply, which enables the price of thepermanent magnet type electric power generator 3 to be reduced bydecreasing amounts of expensive permanent magnets in the permanentmagnet type electric power generator 3 and enables a maximum outputcurve Pt and an approximate output curve Ps to substantially coincidewith each other.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a view for explaining the main circuit of an electrical powergenerating apparatus for dispersed power supply driven by a windmillaccording to the invention;

FIG. 2 is a main circuit diagram of an electric power generatingapparatus for dispersed power supply for explaining the secondembodiment of the invention in the case of the permanent magnet typeelectric power generator including three kinds of windings among whichone winding has a largest number of turns to which the invention isapplied;

FIG. 3 is a main circuit diagram of an electric power generatingapparatus for dispersed power supply for explaining the third embodimentof the invention in the case of the permanent magnet type electric powergenerator including three kinds of windings among which one winding hasthe second largest number of turns to which the invention is applied;

FIG. 4 is a main circuit diagram of an electric power generatingapparatus for dispersed power supply for explaining the fourthembodiment of the invention in the case of the permanent magnet typeelectric power generator has one kind of winding to which the inventionis applied;

FIG. 5 is a diagram for explaining the output of the electric powergenerating apparatus for dispersed power supply of the invention to aconstant voltage power supply such as a battery or the like;

FIG. 6 is a diagram for explaining outputs of the respective windings ofthe first embodiment according to the invention;

FIG. 7 is a diagram for explaining outputs of the respective windings ofthe second embodiment according to the invention;

FIG. 8 is a diagram for explaining outputs of the respective windings ofthe third embodiment according to the invention;

FIG. 9 is a diagram for explaining outputs of the winding of the fourthembodiment according to the invention;

FIG. 10 is a diagram for explaining the output of the electric powergenerating apparatus for dispersed power supply of the prior art to aconstant voltage power supply such as a battery or the like;

FIG. 11 is a diagram for explaining outputs of the respective windingsof the electric power generating apparatus for dispersed power supply ofthe prior art;

FIG. 12 is a diagram for explaining outline of the number of revolutionsof the windmill versus output characteristics of the windmill with windspeeds as a parameter; and

FIG. 13 is a main circuit diagram of the electric power generatingapparatus for dispersed power supply of the prior art.

DESCRIPTION OF THE REFERENCE NUMERALS

-   1 Windmill-   2 Electric power generating apparatus for dispersed power supply-   3 Permanent magnet type electric power generator-   4, 5, 6 First, second and third reactors-   7, 8, 9 First, second and third rectifiers-   10 Capacitor-   11 Positive output terminal-   12 Negative output terminal-   13 Battery

BEST MODE FOR CARRYING OUT THE INVENTION

In a main circuit of an electric power generating apparatus fordispersed power supply including a permanent magnet type electric powergenerator having a plurality of windings inducing different effectivevalues of induced voltages, alternating current outputs of whichelectric power generator are rectified by individual rectifiers whosedirect current outputs are summed up to output to external, according tothe invention a capacitor is connected in series between the rectifierand the alternating current output terminal of the winding inducing thehigh effective value of induced voltage among the plurality of thewindings in a manner that the serial sum of inductive impedance by theinternal inductance of the permanent magnet type electric powergenerator and capacitive impedance by the capacitor becomes capacitiveimpedance within the range of rated rotational speed of said permanentmagnet type electric power generator.

Embodiment 1

FIG. 1 is a view for explaining the main circuit of the electric powergenerating apparatus for dispersed power supply driven by a windmill orwaterwheel to obtain direct current output according to the invention.

In FIG. 1, reference numeral 10 denotes a capacitor, and the samecomponents as those in FIG. 13 are identified by the same referencenumerals as those used in FIG. 13. The main circuit of the electricpower generating apparatus according to the invention will be explainedhereinafter with reference to FIG. 1 and further FIGS. 5 and 6explaining the principle of the invention.

A capacitor 10 and further a second rectifier 8 are connected in seriesto the alternating current output terminal W2 of a second winding havinga larger number of turns. A first reactor 4 and further a firstrectifier 7 are connected in series to the alternating current outputterminal W1 of a first winding having a smaller number of turns.

The outputs of the first and second rectifiers 7 and 8 are connected inparallel to each other, and a battery 13 is charged with the totaldirect current output of the first and second rectifiers.

Now, the capacitor 10 is designed on the basis of the internalinductance of the second winding in said permanent magnet type electricpower generator 3 in a manner that the internal inductance of the secondwinding and the serial impedance of the capacitor 10 become capacitiveimpedance within the range of rated rotational speed of said permanentmagnet type electric power generator 3.

With such designing, the second winding allows alternating current toflow, which is obtained by vectorially summing up the effective currentfor the battery 13 and phase advance current owing to the capacitiveimpedance.

When the number of revolutions N of the windmill is low, the battery 13is not charged because the induced voltage of the second winding islower than the battery voltage Vb.

However, when the number of revolutions N of the windmill increases to avalue near to N2, the electric current starts to flow so that the outputof the second winding becomes P2.

With increase in the number of revolutions N of the windmill, that is,with increase in frequency of the permanent magnet type electric powergenerator 3, the internal inductance of the second winding and theserial impedance of the capacitor 10 will be reduced. Therefore, thealternating current output by means of the second winding increasessubstantially in proportion to square of frequency, in conjunction withincrease in the induced voltage.

Because the phase advance current flows through the second winding,moreover, there is a tendency for gap magnetic flux of the permanentmagnet type electric power generator 3 to be magnetized so that theinternal induced voltages of the first and second windings increase.

FIG. 6 is an explanatory view for the case that the direct currentoutput of the electric power generating apparatus 2 for dispersed powersupply according to the invention is connected to a constant voltagepower supply such as a battery or the like. The respective outputs ofthe first and second windings of the permanent magnet type electricpower generator 3 of the electric power generating apparatus 2 fordispersed power supply are shown as P1 and P2 of the number ofrevolutions of the windmill versus output characteristic curves of FIG.6, owing to the difference in effective values of induced voltages ofthe respective windings and voltage drop due to the internal inductancesof the respective windings and the reactor or capacitor connected toeach of the output terminals.

FIG. 5 is a view illustrating the output to the constant voltage powersupply such as the battery or the like of the electric power generatingapparatus 2 for dispersed power supply according to the invention.

When the number of revolutions N increases, the output of the firstwinding having the smaller internal inductance and the like starts tobecome larger.

Because the phase advance current flows through the second winding, nowthe internal induced voltage of the first winding increases. However,the magnetizing effect by the phase advance current of the secondwinding is restrained by demagnetizing effect due to lagging current ofthe first winding itself, with the increase in the current flowingthrough the first winding.

Accordingly, the total output obtained by summing up the outputs P1 andP2 becomes larger than the approximate output curve Ps of the prior artshown in FIG. 10 so that the output like an approximate output curve Psshown in FIG. 5 can be obtained which is similar to the maximum outputcurve Pt.

Embodiment 2

FIG. 2 illustrates the second embodiment of the invention.

FIG. 2 is a view illustrating the main circuit of an electric powergenerating apparatus for dispersed power supply including a permanentmagnet type electric power generator 3 having three kinds of windingsamong which one kind winding has the largest number of turns to whichthe present invention is applied.

In FIG. 2, reference numeral 9 denotes a third rectifier, and the samecomponents as those in FIGS. 1 and 13 are identified by identicalreference numerals.

The second embodiment of the invention will be described with referenceto FIG. 2 hereinafter.

A capacitor 10 and further a third rectifier 9 are connected in seriesto the alternating current output terminal W3 of the third windinghaving the largest number of turns in the permanent magnet type electricpower generator 3. A second reactor 5 and further a second rectifier 8are connected in series to the alternating current output terminal W2 ofthe second winding having the second largest number of turns. A firstreactor 4 and further a first rectifier 7 are connected in series to thealternating current output terminal W1 of the first winding having thesmallest number of turns.

The outputs of the first to third rectifiers 7 to 9 are connected inparallel to one another, and a battery 13 is charged with the totaldirect current output of the first to third rectifiers.

In this case, the capacitor 10 is designed on the basis of the internalinductance of the winding in said permanent magnet type electric powergenerator 3 in a manner that the internal inductance of the thirdwinding and the serial impedance of the capacitor 10 become capacitiveimpedance within the range of rated rotational speed of said permanentmagnet type electric power generator 3.

With such designing, when the number of revolutions N of the windmillincreases to cause the induced voltage of the third winding to be higherthan the voltage Vb of the battery, the third winding allows alternatingcurrent to flow, which is obtained by vectorially summing up theeffective current for the battery 13 and phase advance current owing tothe capacitive impedance.

With the increase in the number of revolutions N of the windmill, thatis, with the increase in frequency of the alternating current output ofthe permanent magnet type electric power generator 3, the internalinductance of the third winding and the serial impedance of thecapacitor 10 will be decreased. Therefore, the alternating currentoutput by means of the third winding increases substantially inproportion to square of frequency, in conjunction with the increase inthe induced voltage of the third winding.

Because the third winding includes phase advance current, moreover,there is a tendency for gap magnetic flux of the permanent magnet typeelectric power generator 3 to be magnetized so that upon current flowingthrough the third winding, the internal induced voltages of the first tothird windings increase.

However, the magnetizing effect by the phase advance current of thethird winding is restrained by the demagnetizing effect due to laggingcurrent of the first and second windings, with the increase in thecurrents of the first and second windings.

FIG. 7 illustrates the outputs of the respective windings in the secondembodiment of the invention. When the number of revolutions N of thewindmill increases, the outputs of the respective windings areincreased, particularly the output of the third winding being increasedin inversely proportion to the number of revolutions N of the windmillor the frequency.

The total output obtained by summing up the outputs P1 to P3 of thefirst to third windings more approximates to the maximum output curve Ptthan does the approximate output curve Ps in the case of the twowindings shown in FIG. 5, because the permanent magnet type electricpower generator 3 in this embodiment has the three kinds of windings.

Embodiment 3

FIG. 3 illustrates the third embodiment of the invention.

FIG. 3 is a view illustrating the main circuit of an electric powergenerating apparatus 3 for dispersed power supply including a permanentmagnet type electric power generator having three kinds of windingsamong which one kind winding has the second largest number of turns, towhich the present invention is applied and whose alternating currentoutput terminal has a capacitor connected thereto.

In FIG. 3, reference numeral 6 denotes a third reactor, and the samecomponents as those in FIG. 2 are identified by identical referencenumerals.

The third embodiment of the invention will be described with referenceto FIG. 3 hereinafter.

A third reactor 6 and further a third rectifier 9 are connected inseries to the alternating current output terminal W3 of the thirdwinding having the largest number of turns.

A capacitor 10 and further a second rectifier 8 are then connected inseries to the alternating current output terminal W2 of the secondwinding having the second largest number of turns.

A first reactor 4 and further a first rectifier 7 are connected inseries to the alternating current output terminal W1 of the firstwinding having the smallest number of turns.

The outputs of the first to third rectifiers 7 to 9 are connected inparallel to one another, and a battery 13 is charged with the totaldirect current output of the first to third rectifiers.

In this case, the capacitor 10 is designed on the basis of the internalinductance of the winding in said permanent magnet type electric powergenerator 3 in a manner that the internal inductance of the secondwinding and the serial impedance of the capacitor 10 become capacitiveimpedance within the range of rated rotational speed of said permanentmagnet type electric power generator 3.

With such designing, when the number of revolutions N of the windmillincreases to cause the induced voltage of the second winding to behigher than the voltage Vb of the battery, the second winding allowsphase advance current to flow.

Because the phase advance current flows through the second winding,moreover, there is a tendency for gap magnetic flux of the permanentmagnet type electric power generator 3 to be magnetized so that when thenumber of revolutions of the windmill is increased to cause electriccurrent to start to flow through the second winding, the internalinduced voltages in the first to third winding will increase.

FIG. 8 illustrates the outputs of the respective windings in the thirdembodiment of the invention. When the number of revolutions N of thewindmill increases, the outputs of the respective windings areincreased, particularly the output of the second windings beingincreased substantially in proportion to square of the number ofrevolutions N or frequency.

The total output obtained by summing up the outputs P1 to P3 of thesefirst to third windings more approximates to the maximum output curve Ptthan does the approximate output curve Ps shown in FIG. 5, because thepermanent magnet type electric power generator 3 in this embodiment hasthe three kinds of windings.

However, the magnetizing effect by the phase advance current of thesecond winding is restrained by the demagnetizing effect due to laggingcurrent of the first and third windings, with the increase in thecurrents of the first and third windings.

When the capacitor 10 is connected to the second windings having thesecond largest number of turns, much electric current flows through thecapacitor 10 and the internal impedance of the second winding is small.However, this construction has an advantage that a small capacity of thecapacitor 10 is enough to obtain the capacitive impedance within therated rotational speed range, because the range of the number ofrevolutions N of the windmill requiring the flow of the phase advancecurrent is narrow.

Embodiment 4

FIG. 4 illustrates the fourth embodiment of the invention.

FIG. 4 is a view of a main circuit of an electric power generatingapparatus for dispersed power supply including a permanent magnet typeelectric power generator 3 having only one kind of winding to which theinvention is applied.

In FIG. 4, the same components as those in FIG. 1 are identified byidentical reference numerals.

The fourth embodiment of the invention will be explained with referenceto FIG. 4, hereinafter.

A capacitor 10 and further a first rectifier 7 are connected in seriesto the alternating current output terminal W1 of the first winding.

In this case, the capacitor 10 is designed on the basis of the internalinductance of the winding in said permanent magnet type electric powergenerator 3 in a manner that the internal inductance of the firstwinding and the serial impedance of the capacitor 10 become capacitiveimpedance within the range of rated rotational speed of said permanentmagnet type electric power generator 3.

With such designing, when the number of revolutions N of the windmillincreases to cause the induced voltage of the first winding to be higherthan the voltage Vb of the battery, the first winding allows phaseadvance current and effective current to flow. The battery is chargedwith the effective current.

Accordingly, when the current starts to flow through the first winding,the internal induced voltage of the first winding will increase with theaid of the phase advance current.

FIG. 9 illustrates the output of the first winding in the fourthembodiment of the invention, wherein when the number of revolutions N ofthe windmill increases, the output will increase substantially inproportion to square of the number of revolutions N of the windmill orthe frequency.

The output P1 of the first winding does not approximate to the maximumoutput curve Pt. However, because the gap magnetic flux of the permanentmagnet type electric power generator 3 is magnetized, the outputsubstantially similar to the maximum output curve Pt can be obtained ina simpler manner in comparison with the main circuit of an electricpower generating apparatus for dispersed power supply of the prior artto which rectifiers only are connected.

INDUSTRIAL APPLICABILITY

According to the main circuit of the electric power generating apparatusfor dispersed power supply of the invention, even if the number ofrevolutions N of the windmill is great, the approximate output curve Psis caused to substantially coincide with the maximum output curve Pt,while the amount of the costly permanent magnets in the permanent magnettype electric power generator 3 can be reduced so that the price of thepermanent magnet type electric power generator 3 is lowered.

Moreover, as there is the magnetizing effect of the windings of largernumber of turns, even if the number of turns of the winding havingsmaller number of turns is reduced, a required induced voltage can beobtained so that the volume and weight of the permanent magnet typeelectric power generator 3 can be reduced owing to the decrease inwindings and winding space. Therefore, the permanent magnet typeelectric power generator becomes lighter, and the case that thegenerator is enclosed in a nacelle of a propeller windmill, the wholenacelle becomes lighter, which is very useful from a practicalstandpoint.

According to the main circuit of the electric power generating apparatusfor dispersed power supply of the invention, when the permanent magnettype electric power generator is operated at a rotational speed at whichit is desired to obtain the maximum efficiency of the generator, all thecopper loss or resistance loss of the permanent magnet type electricpower generator can be minimized by optimizing the leading current orlagging current of each of the windings.

Moreover, when the internal inductance of the second winding resonateswith the capacitor 10, the impedance becomes only resistance componentso that large current flows therethrough. Therefore, if the capacity ofthe capacitor 10 is determined so as to cause the resonance state at therotational speed of the permanent magnet type electric power generator 3more than its rated rotational speed, an electric braking function canbe obtained which gradually operates to stop the windmill as itsrotational speed increases.

The main circuit of the electric power generating apparatus fordispersed power supply according to the invention does not require ananemometer and an expensive PWM converter and achieves reduction inpermanent magnets in the permanent magnet type electric power generator,thereby enabling the apparatus to be inexpensively manufactured.Moreover, standby electric power required for the PWM converter is notneeded so that production of electricity of the apparatus can beincreased for the year. Accordingly, the apparatus of the invention isvery useful from a practical standpoint.

While the capacitor is connected to the winding of the largest number ofturns or second largest number of turns in the Embodiments 2 or 3,capacitors 10 may be connected to both the windings of the largestnumber and second largest number of turns.

Although the case using the force of wind has been explained, it is tobe understood that hydraulic power may be used and the invention isapplicable to a use employing hydraulic power in which the number ofrevolutions versus output characteristic for the maximum output isprimarily determined upon the shape of a waterwheel being determined.

Moreover, while the invention has been explained with the three phases,single phase and other phases are also applicable.

Furthermore, although the first reactor 4 is connected to thealternating current output terminal W1 of the first winding in theembodiments shown in FIGS. 1 to 3, it is also possible to delete thefirst reactor by designing the permanent magnet type electric powergenerator 3 so that the required inductance value of the first reactor 4becomes smaller.

1. A main circuit of an electric power generating apparatus fordispersed power supply comprising a permanent magnet type electric powergenerator driven by a windmill or waterwheel driven at varying speeds bywind or water, and having two windings, each of said two windingsinducing different effective values of induced voltages, alternatingcurrent outputs of said permanent magnet type electric power generatorbeing rectified by individual rectifiers, and direct current outputs ofsaid individual rectifiers being summed up in parallel to output to anexternal, wherein a reactor is connected in series between a firstindividual rectifier and an alternating current output terminal of afirst one of said two windings, said first winding inducing a lowereffective value of induced voltage among said two windings, and acapacitor is connected in series between a second individual rectifierand an alternating current output terminal of a second one two windings,said second winding inducing a higher effective value of induced voltageamong said two windings, in a manner that a sum of inductive impedanceby internal inductance of the second winding and capacitive impedance bysaid capacitor is capacitive impedance having its absolute value beingdecreased at an increase of number of rotations of the windmill orwaterwheel, within a range of rated rotational speed of said permanentmagnet type electric power generator.
 2. A main circuit of an electricpower generating apparatus for dispersed power supply comprising apermanent magnet type electric power generator driven by a windmill orwaterwheel driven at varying speeds by wind or water, and having twowindings, each of said two windings inducing different effective valuesof induced voltages, alternating current outputs of said permanentmagnet type electric power generator being rectified by individualrectifiers, and direct current outputs of said individual rectifiersbeing summed up in parallel to output to an external, wherein a reactoris connected in series between a first individual rectifier and analternating current output terminal of a first one of said two windings,said first winding inducing a lower effective value of induced voltageamong said two windings, and a capacitor is connected in series betweena second individual rectifier and an alternating current output terminalof a second ones of said two windings, said second winding inducing ahigher effective value of induced voltage among said two windings, in amanner that a sum of inductive impedance by internal inductance of thesecond winding and capacitive impedance by said capacitor is capacitiveimpedance having its absolute value being decreased at an increase ofnumber of rotations of the windmill or waterwheel, within a range ofrated rotational speed of said permanent magnet type electric powergenerator, so that said second winding enables output of alternatingcurrent substantially in proportion to a square of frequency inconjunction with increase in the induced voltage of the second winding.